INCOME TAXES - Components Of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Current:
United States-Federal									$ 15,763	$ (1,308)	$ 14,761
United States-State									505	(383)	1,347
Foreign									10,528	7,959	12,153
Total current income tax expense									26,796	6,268	28,261
Deferred:
United States-Federal									(1,880)	16,760	5,205
United States-State									(291)	1,636	466
Foreign									(3,465)	(527)	(5,784)
Total deferred income tax expense (benefit)									(5,636)	17,869	(113)
Consolidated:
United States-Federal									13,883	15,452	19,966
United States-State									214	1,253	1,813
Foreign									7,063	7,432	6,369
Total Income Tax Expense	$ 3,982	$ 9,602	$ 2,945	$ 4,631	$ 1,482	$ 10,134	$ 13,008	$ (487)	21,160	24,137	$ 28,148
Deferred tax assets:
Receivables reserve	1,470				702				1,470	702
Temporary differences not currently deductible for tax	8,918				7,236				8,918	7,236
Deferred compensation	2,461				2,135				2,461	2,135
Foreign tax credit carryforwards					4,180					4,180
Pension	1,085				1,153				1,085	1,153
Net operating losses	29,571				4,463				29,571	4,463
Total deferred tax asset	43,505				19,869				43,505	19,869
Deferred tax liabilities:
Property, plant and equipment, net	41,136				43,718				41,136	43,718
Intangible assets, net	6,122				13,743				6,122	13,743
Total deferred tax liabilities	47,258				57,461				47,258	57,461
Valuation allowance	(42,462)				(7,814)				(42,462)	(7,814)
Net deferred tax liabilities	(46,215)				(45,406)				(46,215)	(45,406)
Deferred tax assets:
Long term and total deferred tax asset	407								407
Deferred tax liabilities:
Long term and total deferred tax liabilities	(46,622)				(45,406)				(46,622)	(45,406)
Net deferred tax liabilities	(46,215)				(45,406)				$ (46,215)	(45,406)
Period of cumulative loss									3 years
Operating loss carryforward that will expire	83,500								$ 83,500
Operating loss carryforward with no expiration	3,400								3,400
Federal
Deferred tax liabilities:
Operating loss carryforwards	3,300								3,300
State
Deferred tax liabilities:
Operating loss carryforwards	8,900								8,900
NOL carryforward valuation allowance	500				2,000				500	2,000
Foreign
Deferred tax assets:
Tax Credits					4,100					4,100
Deferred tax liabilities:
Operating loss carryforwards	74,700								74,700
NOL carryforward valuation allowance	27,800				$ 1,700				27,800	$ 1,700
Valuation allowance established as part of purchase accounting	41,900								41,900
Remaining valuation allowance applied to other foreign deferred taxes	14,100								14,100
Undistributed earnings of foreign subsidiaries considered indefinitely reinvested	$ 288,600								$ 288,600